On Earth Day, April 22, 2010, of all days, the British mining giant Anglo American is holding its annual shareholder meeting in London. Anglo American and Northern Dynasty Minerals, its Canadian partner, are scheming to construct one of the world's largest copper and gold mines, the Pebble Mine, in the watershed above Alaska's pristine Bristol Bay.

This unspoiled region, surrounded by icy peaks, is made up of vast tundra, crisscrossed by crystal clear rivers, fed by pristine lakes, including Alaska's largest. Moose and caribou wander in fertile wetlands across a jigsaw array of national parks, wildlife refuges, and our country's largest state park. Grizzlies, wolverines, seals and whales, sea birds and bald eagles flourish there in numberless congregations drawn by the lure of tens of millions of thrashing salmon, charging upstream to spawn, feeding the most productive sockeye salmon fishery in the world. For thousands of years, local communities have relied on subsistence fishing and hunting.

Incredibly, the global mining conglomerate Anglo American and its Canadian partner Northern Dynasty Minerals Ltd. (including Rio Tinto and Mitsubishi Corporation) have already invested hundreds of millions of dollars in a plan that would transform this magical Eden into an industrial wasteland. They want to build one of the world's largest gold and copper mines in the heart of Bristol Bay's watershed. Picture a gaping pit two miles wide and 2,000 feet deep, and an underground mine almost a mile deep near the shores of Lake Iliamna, the source that, with the Nushagak River to the north, feeds the entire 40,000-square mile watershed and Bristol Bay itself.

At Bristol Bay's headwaters, the Pebble Mine will spew a witch's brew of toxic waste -- deadly acids from mineralized rock, contaminated leacheate from tailings piles, and the toxic residues from processing chemicals. The mining moguls will detonate thousands of tons of explosives to open the earth, build roads and trample thousands of acres of wilderness and wetland beneath giant vehicles. Project construction will permanently alter the region's natural river drainage system, including de-watering an estimated 60 miles of spawning habitat in the world's largest intact sockeye salmon streams. An 86-mile road will link the mine to a new deepwater industrial port in Cook Inlet, increasing ship traffic and port pollution and further pressuring the Inlet's dwindling population of critically endangered beluga whales. The mine would also threaten beluga whales in Bristol Bay, who depend on the salmon runs for survival. The mine may produce up to 10 billion tons of waste and lethally poisonous mine tailings stored in artificial ponds covering over 10 square miles, behind several of the tallest dams in the world - earthen structures that dwarf even China's concrete and steel Three Gorges Dam. The operation will require as much energy as Anchorage, Alaska's largest city, exacerbating global warming.

This apocalyptic spectacle in one of the world's most treasured ecosystems has mobilized a rare coalition of angry opponents in Alaska, including native communities, commercial and recreational fishermen, hunters, outdoor outfitters, environmentalists, and Alaska's tourism industry. Even prominent jewelers led by Tiffany & Co. aren't buying the conglomerate's claims that their project is safe: Tiffany's announced last year a "No Pebble Pledge" -- a campaign joined by over 20 jewelry companies, with annual sales in the billions.

And their skepticism is a safe bet given the track record of similar large-scale hard rock mines. A recent study found that 89% of such mines in the U.S. violated water-quality standards despite unequivocal permit commitments to comply with state and federal requirements.

The leader of this unusual alliance to protect Bristol Bay is Nunamta Aulukestai ("Caretakers of Our Land" in Yup'ik), an association of native communities around Bristol Bay that have relied for millennia on subsistence fishing and hunting. Nunamta has partnered with Alaska's commercial and recreational fishermen to protect the cradle of what is arguably Alaska's most valuable renewable resource - the Fort Knox of salmon -- generating tens of thousands of jobs and over $400 million in revenue each year. Because copper is toxic to fish, even minute exposures risk impairing their navigational systems, destroying a salmon's ability to return to its spawning stream, and thereby jeopardizing all of the native communities around Bristol Bay and the region's wildlife that rely on annual salmon returns.

The Pebble Mine threatens southwest Alaska's natural resources, the economic foundation of communities throughout Bristol Bay, and our shared interest in the security of a food supply of national importance. Pebble is a toxic recipe for disaster, and it should be abandoned now. There are a lot of places in the world to mine copper and gold. But there is no compelling reason to allow a foreign consortium to destroy one of America's great national treasures and jeopardize the health and livelihood of American citizens.